The present invention relates to an industrial robot, and more particularly, to an industrial robot which is employed in workplaces involved in processing, manufacture, transfer, packaging, dispatch, or the like, of products relating to foodstuffs, medical care or hygiene.
An industrial robot (hereinafter, simply referred to as xe2x80x9crobotxe2x80x9d) involves in its structure a large number of mechanical elements, such as speed reducers, gears, ball screws, bearings, linear guides, and the like, in its moving parts. In order to maintain smooth movement of the mechanical elements used in these moving parts, it is common to use a mineral lubricating oil. This lubricating oil is introduced and held in a sealed structure provided in the robot mechanisms, and it is necessary to change the lubricating oil when it deteriorates, even if it is supposed that the oil is sealed and held in a complete manner, and the lubricating oil is liable to leak or scatter outside while being discharged and replenished. Moreover, the same possibility arises when parts in the vicinity of the region where the lubricating oil is held are serviced, inspected, changed, or the like.
Therefore, when a conventional robot is used in a workplace involved in processing, manufacturing, transferring, packaging, shipping, or the like, relating to foodstuffs, medical care or hygiene, it is extremely difficult to eliminate completely the possibility of mineral-type lubricating oil adhering to or infiltrating the foodstuff, medical or hygiene-related products handled by the robot, or the wrapping or packaging thereof.
Furthermore, a large number of seals, such as oil seals, and the like, are used in the moving parts of robots, for the purpose of preventing leakage of lubricating oil or infiltration of dust, and with their wearing and deterioration, leaking of lubricating oil is also liable to occur.
Moreover, in general, rubber materials are used for seals, and it is not possible to avoid generation of powder from the rubber as the seals wear. However, generally used rubber-based materials contain a considerable amount of harmful substances, and there is a risk that the powder of rubber material due to wearing, which is discharged from externally exposed seals, may adhere to or infiltrate the foodstuff, medical or hygiene-related products being handled, or their wrapping or packaging, and the like, thereby causing their contamination.
Since the aforementioned mineral lubricating oil and the powder of rubber material caused by wearing, which may possibly be discharged or leak outside, contain substances which are harmful to human bodies when absorbed, then in cases where a conventional robot is used in tasks of handling products relating to foodstuffs, medical care or hygiene, it is difficult to guarantee safety. and a large burden is involved in servicing and inspection tasks. Consequently, this has been a major drawback to the introduction of robots into the fields where it is required that any substances discharged are entirely harmless, such as the field of manufacturing and processing food products.
It is an object of the present invention to provide a robot which is suited to tasks which require that any substances discharged are entirely harmless, such as the tasks of manufacturing, transferring, wrapping, packaging and the like of products related to foodstuffs, medical care, hygiene, and the like.
In order to achieve the aforementioned object, the industrial robot according to the present invention is an industrial robot to be employed in a workplace involved in processing or manufacturing of foodstuffs, comprising a sealed structure in the robot mechanism, wherein a harmless lubricating oil, such as polyurethane-base lubricating oil, is used in the mechanical elements contained inside the sealed structure.
Further, a material which is not harmful to human bodies, such as nitrile rubber, fluorine resin or the like, is used for the seals included in moving parts.
Since the robot according to the present invention uses lubricating oil and seals which are safe for human bodies in the mechanical elements incorporated into the moving parts thereof, it is possible to avoid the danger of causing a discharge of lubricating oil or powder produced by wearing of the seals that are harmful to human bodies, even if the robot is used in the tasks of processing, manufacturing, transferring, wrapping, packaging, etc. of products relating to foodstuffs, medical care or hygiene. Moreover, according to the present invention, by making a robot harmless in terms of the substances discharged thereby, a factor impeding the introduction of robots into the aforementioned tasks can be removed.